The present invention relates to improvements in and/or relating to mineral breakers.
Our mineral breaker was first disclosed in Australian Patent Specification No. 463819. Such a mineral breaker was revolutionary at the time since it embodied a system whereby a plurality of the mineral beds are defined within a rotating element (rotor) thus ensuring the majority of the wear (save for a hardened wear tip) is of mineral against mineral.
Enhancements of the original machine are disclosed in our U.S. Pat. No. 4,662,571 (NZ198307), U.S. Pat. No. 4,586,663 (EPO 101277 and NZ201190), U.S. Pat. No. 4,575,013, (NZ 201418), U.S. Pat. No. 4,921,173 (NZ213510), and WO 95/11086 (NZ 250027).
Our U.S. Pat. No. 4,586,663 discloses an improvement whereby, as an enhancement, a hardened wear tip blade is mounted within a recess at the edge of a carrier which is to be positioned at a position where, in the manner of a weir, the smaller pieces of mineral overflow to exit the device.
U.S. Pat. No. 2992783 (Wirth et al) also show a mineral breaker of a kind having a substantially vertical axis feed into a rotor.
U.S. Pat. No. 4940188 of J Rodriguez and D Rodriguez discloses yet a further refinement of the system. This U.S. Patent discloses the use of a weir member which acts substantially as a straight edged wear tip but which better manages the weir erosion.
New Zealand Patent Specification 248953 (WO 95/10358) Tidco International Limited discloses yet a further refinement of the weir tip aspects.
In our WO 95/11086 there is disclosed and claimed a variety of tip defining assemblies for inclusion in a rotor of such a mineral breaker, the weir-like edge being configured, assembled or otherwise arranged to provide a region of flow enhancement such that a greater depth of mineral pieces passes over that edge region favoured to be eroded and to retain a bed of material having a transverse surface conforming to the weir-like edge. Symmetric contours for such a weir-like edge are defined with the preferred forms being to a V, U or other scalloped configuration.
Attention is also drawn to our U.S. Pat. No. 5,911,370 and to our patent specification WO98/56508.
The present invention is therefore directed to providing at least one of a number of possible advantages through localising or focusing the radial high energy streams from the rotor in a rotary mineral crusher where such output high energy materials are to impact mineral pieces within a surrounding crushing chamber. Preferably such a chamber is lined with a lining or bed of mineral pieces (irrespective of whether or not there is a secondary or by-pass flow of other pieces into such a chamber that by-passes the rotor) and from which chamber there is an exit for at least one stream of material of reduced average particle size to that of the original infeed material into the rotor and/or by-passing the rotor into the crushing chamber.
Accordingly in a first aspect the invention consists, in a rotary mineral crusher, a method of any one or more of
(i) localising wear on a wear tip in the crusher,
(ii) focusing the output of the rotor into its interaction chamber, and
(iii) reducing mineral erosion of the exterior of the rotor by mineral particles energised by the output from the rotor,
said rotary mineral crusher being of a kind having a rotor into which mineral pieces to be reduced in size (ie: xe2x80x9ccrushedxe2x80x9d) is fed from above and at least substantially axially of the axis of rotation of the rotor to thence migrate on an acceleration locus or loci of migration via a retained bed or retained beds of mineral pieces from the rotor substantially radially of the rotor into a surrounding interaction chamber capable of retaining a lining of the mineral material,
said method comprising or including
retaining the or each rotor retained bed of mineral pieces with weir-like means defining a sacrificial edge (the xe2x80x9cwear tipxe2x80x9d) over at least substantially the transversal extent of the migration locus at each such edge, said sacrificial edge being of a form which allows an enhanced outflow of mineral pieces over a preferred region of the sacrificial edge without reliance for such enhanced outflow on a symmetric xe2x80x9cVxe2x80x9d, xe2x80x9cUxe2x80x9d, or scallop form, and
configuring the means to retain the lining of mineral pieces of the surrounding interaction chamber so as to provide a preference for interactions of mineral pieces in a zone of the surrounding chamber adequately lined with such mineral pieces, and
optionally, providing shielding means to at least substantially confine the mineral pieces of the interaction zone from the rotor save over the enhanced outflow focused band(s) thereof at least towards the retained lining of mineral pieces of said surrounding interaction chamber.
Preferably there is the additional step of providing interaction zone confinement means (eg: shielding means) to reduce the opening available for the outflow stream of mineral pieces to enter into the surrounding interaction chamber with its retained mineral piece lining.
Preferably said interaction zone confinement means are stationary.
Preferably said interaction zone confinement means is or are in addition to said shielding means.
Preferably said shielding means is or are stationary.
In a further aspect the present invention consists in a rotary mineral crusher modified so as to perform inevitably a method as previously set forth.
In still a further aspect the present invention consists in, in a rotary mineral crusher,
the provision of
a rotor in to which mineral to be crushed is fed at least substantially axially of the substantially horizontally rotating rotor to thence migrate on an acceleration locus (or loci) of migration via a weir-like member/assembly retained bed of mineral pieces (or a plurality thereof) to flow from the rotor substantially radially of the rotor, and
a surrounding interaction zone defined by static means capable of retaining a lining of mineral pieces,
the construction and arrangement being such that each said weir-like member/assembly provides other than with a simple vertical sacrificial (preferably hardened edge) over the fall transverse extent of said migration locus at such edge means (not a symmetric xe2x80x9cvxe2x80x9d, xe2x80x9cuxe2x80x9d or scallop form but can be a straight edge that is not vertical or parallel to the rotor axis) which enhances the outflow of mineral pieces over one specific region of such edge or several specific regions of the edge.
Preferably said lining of mineral pieces are confined by means, top and/or bottom, to reduce the opening to the lining for the outflow stream of mineral pieces.
Preferably there is shielding means between said rotor and the lining to at least reduce contact of the rotor by mineral pieces once they have entered the interaction zone.
Preferably the arrangement is as depicted in any one of the following drawings. Preferably said weir-like member/assemblies are in any of the form insofar as type, material, or mounting is concerned as defined in any one of the earlier mentioned patent specifications but which are asymmetric in the form of the edge when viewed as it will be positioned into the locus of migration eg; half a v, half a u or some other scallop form (eg; a step form).
As used herein throughout the terms xe2x80x9ccrushingxe2x80x9d, xe2x80x9cmineralxe2x80x9d, are to be construed broadly. xe2x80x9cMineralxe2x80x9d includes within its scope any material capable upon mutual collision with like materials of disintegrating into smaller pieces. xe2x80x9cCrushingxe2x80x9d clearly embodies other than crushing under sheer weight. xe2x80x9cCrushingxe2x80x9d is used to describe size reduction as a result of single or multiple interactions between different pieces of the material.
In a further aspect the present invention consists in a method as previously defined comprising the additional step of providing means to reduce the opening available for the outflow stream of mineral pieces to enter, (e.g. preferably one or two lips) into the crushing chamber with its retained mineral piece lining.
In addition preferably there is the step (by providing a shroud or shield that remains during use in fixed relationship with the means that retains the lining) of minimising the effect of rebounding mineral pieces or deflected mineral pieces on the exterior of the rotor at least on those surfaces thereof above and below any at least one circumferential or peripheral port defined adjacent or in part by said weir-like member(s)/assembly(s).
In still a further aspect the present invention consists in apparatus and/or method(s) substantially as herein described with reference to any one or more of the accompanying drawings.
In a further aspect the present invention consists in a tip defining component or assembly for inclusion in a rotor of a mineral breaker, said tip being engageable directly to or via a holder to the rotor to define a weir-like edge that extends substantially transversely of the direction from which mineral pieces in use are to overflow from a retained bed thereof, said edge being characterised in that it is configured, assembled or otherwise arranged to provide a region of flow enhancement such that a concentrated stream of mineral pieces passes preferentially over that part of the edge region, said weir-like edge not being symmetric in that transverse view.
Preferably the top defining component or assembly is of any of the kinds generally as described in any one of the aforementioned patent specifications but which includes therein a change configuration to at least the primary wear tip thereof so as to provide by its asymmetry the desired concentration or focusing of the stream.
The present invention also consists in the use of apparatus of the present invention.
To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.